Conduit for electrical conductors.



F. D. SAYLOR. CONDUIT FOR ELECTRICAL CONDUUTORS. APPLICATION FILED 313.26, 1910.

1,049,771. Patented Jan. 7, 1913.

" UNITED sTAr s PATENT oFFrcn- FRANK D. SAILOR, OF PITTSBURGH, PENNSYLVANIA i CONDUIT FOR ELECTRICAL CONDUCTORS.

To all whom'z't may concern:

Be it known-that I, FRANK D. SAxLoR, a

citizen of the United States, residing at ting to form a continuous smooth interior and exterior; wrapping threads laid spirally around the tube as thus formed in rocess; a coating of tarry or other similar bituminous material; covering strips 'of fibrous material laid spirally around the tube and embedded in said coating with intervenin'g spaces through which .the coating exudes, and a final covering of woven fabric and an outer coating therefor.

.In the drawings :-Figure 1 represents the operation of forming the initial inner tube upon amandrel and the application ofthe wrapping threads. Fig. 2 is a cross sectional view on the line 11. II. of Fig. 1. Fig. 3 is a view of thetube showing successive portions of the same broken away and illustrating the successive layers and the application of the same. Fig. 4 is an enlarged cross sectional view'through a finished tube on the. line IV. IV. of Fig. 3.

In the operation of making the tube, a- ,flat strip 2 of any suitable fabric as woven cloth, canvas or duck, is formed upon a mandrel 3 into a tube 4, the edges of which abut as indicated at 5 whereby to provide a continuously smooth exterior and interior, the

4 strip 2 having been previously treated with a solution of alum, silicate of soda, and powdered mica or other non-inflammable substance to render it fireproof. The advantage of this construction is that in the finished tube the interior is completely cir- ,cular, offering no obstructions or inequalities to interfere with the passage of the elec- 'trical conductors when introduced, while the exterior .is also truly cylindrical, insurmg the cylindrical form of the resulting Speeifieation'of Letters Patent.

Patented Jan."7, 1913.

Application filed February 26,1910. Serial No. 546,115.

completed tube, and facilitating the compact and evenapplication'of the successive layers of material. As the longitudinal strip of fabric 2 is thus formed into the cylindrical I tube and while still upon the mandrel 3, it

is Wrapped by threads 6, 6, preferably two such threads being employed, laid around the tube-in-process spirally as indicated, whereby it is retained in cylindrical shape. The application of threads 6 is accomplished by any suitable loom mechanism to insure regularity of application, the spiral winds thereof being sufiiciently closely adjacent to retain the tube in shape during the succes 'sive steps of operation. The formed tube of fabric is then passed longitudinally'through a bath of covering substance composed of Caladium, pitch and asphaltum, receiving the coating 7 and while such coating is still in a plastic or semi-plastic condition, the

tube as thus coated is annularly wound by any suitable applying mechanism with the spirally arranged strips or hands 8, 8. Said strlps are of fabric or duck, or of any suit-- able fibrous material as preferred, cut into sultable width from sheets of the goods which have preferably been soaked or invested in a mixture of glue and cement.

The cement which is of mineral constituency, completely impregnates the fabric so that the resulting strips 8 are thoroughlycharged or soaked with it, which 'with the proper proportion of glue, renders the resulting strips somewhat stifi', strong and non-combustible, and having the qualities of insulation.

The fact that the coating 7 is applied by dipping the tube in a bath or passing it therethrough, clearly shows that itis fluent and the material itself, to wit, Caladium desired pitch and asphaltum, v maintains .the soft,

plastic quality to the desired degree, after application, In other words, the material does not harden, but remains in asomewhat jelly-like condition of sufficient firmness to retainv its shape, but still subject to pressure of any considerable degree.

'As clearlyshown in Fig. 3, the strips are spirally wound around the tube with slight intervening s aces, through which exudes the tar as indlcated at 9. By this construetion the strips are firmly embedded in the coating '7 so that the initial inner tube 4,

coating 7 and strips 8 are thus closely and intimately associated, forming a cylindrical wall of sufli'cient thickness and strength, and

having an ample degree of flexibility. These qualities are due to the character of the materials employed and also to an extent to the manner of applying the strips 8 by winding them spirally with the intervening spaces. The tube as thus formed is then covered with an outer woven fabric 10 ap plied by a suitable loom in the manner customary in this art, and is then covered with a coating consisting of mica and glue or other adhesive material 11, and the finished tube as thus made is ready for use. Its advantages result from the complete insulation, flexibility, smooth interior, and "noncombustibility, and in practice it has proved to be highly eflicient and well adapted to the objects in view.

Having described my invention, what I claim is 1. An armoring tube for conductors consisting of an inner tube of fabric formed of a longitudinal strip having a straight seam formed by abutting edges, spirally wound fine retaining threads laid around said inner tube, a coating of soft plastic material surrounding said tube and thread wrapping, an inclosing spirally wound fabricated strip covering laid tightly around said coating with intervening spiral spaces and suflicient pressure to form intervening exuding ridges of said plastic material, a woven sheathing of fabric surrounding said spiral winding and exuding ridges and compactly embracing the same, and an outer adhesive finishing coating of covering material, substan-' tially as set forth.

2. An armoring tube for conductors consisting of an inner tube of fabric formed of a longitudinal strip having a straight seam formed by abutting edges, spirally wound fine retaining threads laid around a said inner tube, a coating of soft plastic material surrounding said tube and thread wrapping, a plurality of spirally wound and spaced cement and glue invested fabric strips laid tightly around said coating with suflicient pressure to form intervening exuding ridges of said plastic material, a woven sheathing of fabric surrounding said spiral winding and exuding ridges and compactly embracing the same, and an outer coating of mica and glue, substantially as set forth.

I 3. An armoring tube for conductors consisting of an inner fabric tube, a coating of soft plastic material surrounding said inner fabric tube, an inclosing spirally wound fabricated strip laid tightly around said coating with intervening spiral spaces whereby the plastic material fills the spiral spaces and exudes therefrom, and a woven sheathing of fabric surrounding said spiral winding and exuding plastic material and compactly embracing the same, substantially asset forth.

4.-. In a flexible conduit for electrical conductors, the combination of an inner textile tube, a strip or ribbon of suitable flexible material wound spirally thereon with the edges of adjacent convolutions spaced from each other, an outer textile covering, and a coating of tar surrounding the inner tube and extending through the spaces of the spiral strip into contact with the outer textile covering, substantially as set forth.

5. In a flexible conduit for electrical conductors, the combination of an inner textile tube, a strip or ribbon of suitable flexible material wound spirally thereon with the edges of adjacent convolutions spaced from each other, an outer textile covering, and a coating of tarry material surrounding the inner tube and extending through the spaces of the spiral strip into-contact with the gutefi textile covering, substantially asset ort ture in presence of two witnesses.

FRANK D. SAYLOR. Witnesses:

G. M. CLARKE, CHAS. S. LEPLEY. 

